Preheat broiler.

Slice tomatoes a half-inch thick; place in a single layer on a plate or tray and season with salt and pepper and let sit until needed. Cook bacon until it is crisp; drain and reserve drippings for another use. 

Spread one side of four pieces of bread with brie. Arrange on baking sheet and broil until cheese is soft; do not brown. Top each with four slices of bacon, pressing down into melted cheese. Top each with seasoned tomato and basil. Spread remaining four slices of bread with mayonnaise, and top sandwiches.

Heat a cast-iron skillet over medium-high heat and melt two pats butter. Add two sandwiches to the pan and cook, pressing down with a spatula, until golden brown. Flip and repeat, adding extra butter if needed. Repeat with remaining sandwiches; serve warm. Serves 4.

Tip: Perfect Bacon 

Anyone who has ever fried bacon has sworn out loud after being burned by popping, spattering bacon grease, and while swabbing it off the stovetop and surrounding cabinets. But, bacon is bacon, so we cook it and swear. 

Next time, try this method: Preheat oven to 375ºF. Flatten strips of bacon on a baking sheet and roast for 20 minutes undisturbed (the bacon will stick a bit, making it easier to drain). Carefully remove the pan from the oven and tilt to drain fat into a small bowl; set drippings aside for other uses. Return the bacon to the oven and roast an additional eight minutes or until bacon is browned and crisp. Drain on paper towels; gloat over your spatter-free arms and stovetop.